These States Are Most Exposed to Summer Dehydration Risk 

Dehydration occurs when you lose more fluids than you take in. Primary risk factors include illnesses causing vomiting or diarrhea, excessive sweating from heat or exercise, uncontrolled diabetes, and certain medications like diuretics. Specific age groups, like babies and older adults, are also highly vulnerable. 

Medical Conditions & Illnesses

• Gastrointestinal distress: Severe or prolonged vomiting and diarrhea cause massive fluid and electrolyte losses in a very short time. 
• Fever: An elevated body temperature increases your metabolism and breathing rate, causing you to breathe out and sweat out more moisture. 
• Diabetes: Uncontrolled high blood glucose causes frequent urination, rapidly depleting the body’s fluid levels. 
• Kidney & Chronic Diseases: Conditions like chronic kidney disease, cystic fibrosis, or inflammatory bowel diseases (like Crohn’s) impair the body’s ability to retain or process fluids. 
• Skin injuries: Extensive burns or serious wounds damage the skin barrier, leading to immense fluid loss.

Medications & Substances

• Diuretics: Commonly referred to as “water pills” or blood pressure medicines, these directly increase urination.
• Alcohol: Alcohol acts as a diuretic, inhibiting vasopressin (a hormone that helps your body retain water) and accelerating fluid loss. 

Environment & Lifestyle

• Hot & Humid Weather: High temperatures and humidity cause you to sweat heavily. Sweat cools the body but rapidly drains fluid reserves if not actively replenished. 
• Strenuous Exercise: Vigorous physical activity and manual labor cause heavy sweating, which can lead to rapid dehydration if you do not consistently replace both water and lost electrolytes. 
• Lack of Access: Simple unavailability of safe drinking water (e.g., during outdoor adventures) is a frequent cause of dehydration. 

Vulnerable Populations

• Infants & Young Children: Their smaller body weights make them extremely sensitive to even minor fluid losses, and they are prone to frequent diarrhea and vomiting.
• Older Adults: As you age, natural physiological changes can diminish your ability to sense thirst, causing you to drink less water than your body actually needs.
• Breastfeeding Mothers: Producing breastmilk uses additional fluids and electrolytes, meaning nursing mothers must consciously increase their daily water intake to avoid dehydration. 

These States Are Most Exposed to Summer Dehydration Risk 

Key Highlights

Arizona residents will be at the biggest risk of dehydration in the summer, a June 2026 report finds. A new study by Instant Hydration reveals where Americans need to be most careful about drinking enough water as temperatures climb.

• Dehydration kills more people in Arizona than anywhere else, claiming over 1,500 lives in the past six years.
• Texas sees 107 days above 90°F every year, exposing millions to months of dangerous heat.
• At 42.5% humidity, Nevada is one of the driest places in America, causing residents to dehydrate fast without feeling thirsty.

The research examined five factors that cause dehydration across all 50 states. This included the number of days above 90°F each year and humidity levels that determine how fast people lose water through sweat. The report also tracked heat deaths over six years, looked at how many homes have air conditioning, and measured water usage. States received a dehydration index score from 0 to 100, where higher numbers mean greater risk.

Top 10 States Most at Risk of Summer Dehydration

You can access the complete research findings here.

A Closer Look at the Top 5

1. Arizona

• Dehydration Risk Index: 100/100
• Heat days annually: 116
• Average humidity: 38%
• AC penetration: 94%
• Heat deaths 2018-2024: 1,563 total

Arizona residents are at the biggest risk of dehydration during the summer heat. The desert climate here leads to 116 days above 90°F each year, nearly a third of the calendar. But what makes Arizona especially risky is the 38% humidity, the second-lowest in the country. In dry air like this, sweat evaporates before you notice it, so your body loses water without triggering the thirst response. As a result, over 1,500 people died from dehydration and heat exposure in the past six years here, more than in any other state. 

2. Nevada

Nevada comes second as another desert state where dry air masks dehydration. The state records 82 scorching days annually, and with humidity sitting at just 42.5%, residents here can lose fluids faster than they realize. This often leads to fatal cases, with more than 540 people dying from dehydration over the past six years. To escape the heat, 92% of Nevada homes run air conditioning throughout summer, but the cooled indoor air actually makes dehydration worse by drying people out even more while they’re inside.

3. Texas

Texas ranks third in dehydration risks. The state sees 107 days of heat each year, making it one of the driest places in America. Plus, unlike Arizona and Nevada, Texas has 63% humidity, which creates a different kind of danger. The sticky air makes people sweat nonstop, causing them to lose water much faster than they realize. In the past few years alone, 772 Texans have lost their lives due to these extreme weather conditions.

4. New Mexico

New Mexico ranks fourth, recording 59 days above 90°F annually. The state also records 41% humidity, putting it in the same dry-heat zone as Arizona, where sweat vanishes before you feel it. Making things worse, New Mexico has nearly two times lower water usage than Nevada, indicating that residents here might not be drinking enough water to replace what their bodies lose during the summer heat. 

5. Oklahoma

Oklahoma rounds out the top five states at the biggest risk of dehydration in the summer. The state records 92 days above 90°F each year, nearly a third of the calendar. At 63.5% humidity, people here also face conditions similar to those in Texas, where the sticky air makes them sweat constantly, draining water from their bodies faster than they realize. Plus, air conditioning is nearly universal at 96%, meaning residents spend most of their time in dry indoor air that pulls even more moisture from their bodies. 

The wellness expert from Instant Hydration commented on the study:

“Dehydration in dry climates works differently. In Arizona or Nevada, you can lose a liter of water through your skin in an hour and never feel sticky or thirsty. Your brain uses wetness as a signal to drink more water, but when sweat evaporates instantly, that signal never fires. People working outside in Phoenix may not realize they’re dehydrated until they start feeling dizzy or getting headaches, and by that point, they could already be in trouble.”

To Prevent Dehydration

Prevent dehydration by consuming adequate fluids daily, sipping water consistently rather than chugging large amounts at once, and eating water-rich foods like fruits and vegetables. Adjust your intake upwards in hot weather, when ill, or during physical activity. 

Daily Intake Strategies

• The baseline: Aim for 64 to 80 ounces (8–10 glasses) of fluid daily, but increase this if you are active or in hot environments.
• Make it routine: Keep a reusable water bottle nearby. Sip throughout the day rather than waiting until you feel thirsty.
• Eat your water: Up to 20% of your daily water intake comes from food. Snack on cucumbers, watermelon, strawberries, and peaches.
• Check your urine: The simplest hydration test is checking your pee. Aim for a pale, straw, or lemonade color. Darker yellow signals the need to drink more. 

Exercise and Heat

• Pre-hydrate: Drink 16–20 ounces of water about 1–2 hours before beginning outdoor or strenuous activities.
• During activity: Drink about 6 ounces every 10–15 minutes. If sweating heavily for over an hour, consider an electrolyte or sports drink to replace sodium.
• Post-activity: Drink at least 16–24 ounces after exercising to replace lost fluids.

What to Avoid

• Diuretics and sugars: Limit alcohol, sodas, and drinks high in caffeine and added sugars. These act as diuretics, pulling fluid out of your body. 

Hydrating When Sick

• Sip small and steady: If dealing with a fever, vomiting, or diarrhea, take small, frequent sips of water.
• Ice chips: If you are too nauseated to drink, try sucking on ice chips or sugar-free popsicles.
• Electrolyte solutions: For severe illness, utilize oral rehydration solutions (like Pedialyte) to replace essential salts and sugars. 

For personalized advice or information regarding hydration and fluid limits—especially if you have conditions like heart failure or kidney issues—consult your health care provider.

This article was created at the WHN News Desk in collaboration with Mia Nelson on behalf of Instant Hydration, with 7x the electrolytes of leading sports drinks, their premium formula — powered by naturally superior sel gris — gives your body & mind everything it needs to perform at your peak, instantly. 

As with anything you read on the internet, this article should not be construed as medical advice; please talk to your doctor or primary care provider before changing your wellness routine. WHN neither agrees nor disagrees with any of the materials posted. This article is not intended to provide a medical diagnosis, recommendation, treatment, or endorsement. Additionally, it is not intended to malign any religion, ethnic group, club, organization, company, individual, or anyone or anything. These statements have not been evaluated by the Food and Drug Administration.